Fluid environment in a treatment zone

ABSTRACT

The transfer of energy in a fluid environment in a treatment zone is closely controlled by carefully controlling the enthalpy of the incoming fluid environment and the enthalpy of the exhausting fluid environment. The enthalpy in the incoming fluid environment is controlled independently of the enthalpy of the treatment zone. The enthalpy in the exhausting fluid environment is controlled in response to the temperature of the exhausting fluid environment. Carbonaceous or inert material or both may be added to the fluid environment to control the temperature of the exhausting fluid environment. The fluid environment may be a saturated fluid mixture composed of liquid water saturated with a major amount of carbon dioxide, a minor amount of methane (which may be omitted), and lesser amounts of hydrogen and carbon monoxide at temperatures from about 32*F to about 160*F and at pressures up to the equilibrium pressure of water, 218.5 atmospheres. When using a saturated fluid mixture for the treatment environment, best results are obtained when the temperature of the exhausting environment is maintained within the range of about 212*F to about 1,500*F, the preferred ranges being for low water concentration mixtures from about 212*F to about 400*F and for higher water concentration mixtures from about 400*F to about 980*F. The method is applicable to other fluid environments, for example, inert gases, such as argon, or reducing gases, such as hydrogen, or nitriding gases, such as nitrogen, or carburizing gases, such as methane, or controlled fluid mixtures, such as endothermic or exothermic environments. A number of examples is set forth.

United States Patent [191 Ingels 1 July 10, 1973 FLUID ENVIRONMENT IN ATREATMENT ZONE [76] Inventor: Glen R. Ingels, 9940 Memorial Drive,Houston. Tex. 77024 [22] Filed: May 8,1972

21 Appl. No.: 250,923

Related 1.1.8. Application Data [63] Continuation-impart of Ser. No.828,600, May 28, 1969, abandoned, which is a continuation-in-part ofSer. No. 597,291, Nov. 28, 1966, abandoned, which is acontinuation-in-part of Ser. No. 292,280, July 2, 1963, abandoned.

Primary Examiner3ohn J. Camby Attorney-James F. Weiler et a1.

[57] ABSTRACT The transfer of energy in a fluid environment in atreatment zone is closely controlled by carefully controlling theenthalpy of the incoming fluid environment and the enthalpy of theexhausting fluid environment. The enthalpy in the incoming fluidenvironment is controlled independently of the enthalpy of the treatmentzone. The enthalpy in the exhausting fluid environment is controlled inresponse to the temperature of the exhausting fluid environment.Carbonaceous or inert material or both may be added to the fluidenvironment to control the temperature of the exhausting fluidenvironment. The fluid environment may be a saturated fluid mixturecomposed of liquid water saturated with a major amount of carbondioxide, a minor amount of methane (which may be omitted), and lesseramounts of hydrogen and carbon monoxide at temperatures from about 32Fto about 160F and at pressures up to the equilibrium pressure of water,218.5 atmospheres. When using a saturated fluid mixture for thetreatment environment, best results are obtained when the temperature ofthe exhausting environment is maintained within the range of about 212Fto about 1,500F, the preferred ranges being for low water concentrationmixtures from about 212F to about 400F and for higher waterconcentration mixtures from about 400F to about 980F. The method isapplicable to other fluid environments, for example, inert gases, suchas argon, or reducing gases, such as hydrogen, or nitriding gases, suchas nitrogen, or carburizing gases, such as methane, or controlled fluidmixtures, such as endothermic or exothermic environments. A number ofexamples is set forth.

l6 Claims,.8 Drawing Figures Patented July 10, 1973 4 Sheets-Sheet l m.w m mfw u/ M;

Patented JuEy 3%, 31973 4, Shects-5hcet a 11% un. hi hwl ns! Hl l fl llle My Patented Juiy 10, 1973 4 Sheets-Sheet '1 fan may BY y {a p awrKlf/OF/YEVJ FLUID ENVIRONMENT IN A TREATMENT ZONE CROSS REFERENCE TORELATED APPLICATIONS This application is a continuation-in-part ofapplication Ser. No. 828,600 filed May 28, 1969, now abandoned which isa continuation-in-part of application Ser. No. 597,291 filed Nov. 28,1966, now abandoned, Which is a continuation-in-part of application Ser.No. 292,280 filed July 2, 1963, now abandoned, in which restriction wasrequired. Claims to other inventions disclosed and claimed herein areincluded in U. S. Pat. No. 3,539,165 granted Nov. 10, 1970 issued onapplication Ser. No. 833,308 filed June 16, 1969, which is acontinuation-in-part of application Ser. No. 597,290, Nov. 28, 1966,abandoned, which is a continuation-inpart of application Ser. No.292,280, July 2, 1963, abandoned; and continuation-in-part ofapplication Ser. No. 590,290 filed Nov. 28, 1966, now abandoned, andStreamlined Continuation application Ser. No. 28,192 filed Apr. 4, 1970of Ser. No. 7 l9,6l 3 filed Jan. 8, 1966, now U.S. Pat. No. 3,655,172,which is a continuation-in-part of application Ser. No. 604,515 filedNov. 28, 1966, now abandoned which in turn is a continuation-impart ofapplication Ser. No. 292,280 filed July 2, 1963 now abandoned.

BACKGROUND OF THE INVENTION The present invention relates to methods ofcontrolling the transfer of energy in a fluid environment in a treatmentzone. More specifically, the present invention relates to methods oftransferring energy in a fluid environment in a treatment zone bycarefully controlling the enthalpy of the incoming fluid environment andthe enthalpy of the exhausting fluid environment. The methods are usefulin the reduction, melting, heat treating, welding, cold treating,casting, surface treating, and the like of metallic and nonmetallicbodies by which advantageous properties in the material are obtained.

It has long been desired in the art to provide a method or system fortreating metals and nonmetals in a suitable fluid environment by whichvery exact control conditions in the furnace are obtained so thatdesired properties can be imparted to these metals and nonmetals. In themetallurgical art until the present development, there was no method orsystem for treating metals and nonmetals in which the enthalpy of theincoming fluid environment, for example, the temperature and thepressure of the fluid environment are controlled in a preheater prior toentrance to the treatment zone of a furnace and the enthalpy of theexhausting fluid environment is controlled, for example, the temperatureor energy level of the fluid exhausting from the treatment zone of thefurnace is controlled, by which very exact control conditions in thefurnace are obtained so that the desired energy of the fluid environmentis transferred to the metals and non-metals thereby imparting to themdesired properties.

It also has been desired in the art to treat metals and nonmetals in afluid environment which may be in equilibrium or neutral to them, may beoxidizing and decarburizing, oxidizing and carburizing, reducing anddecarburizing or reducing and decarburizing under operating conditions.

The present invention is directed to such methods and treatment.

SUMMARY The present invention relates to methods of control ling thetransfer of energy in a fluid environment in a treatment zone by whichhighly desired properties are imparted to materials being treated. Thepresent invention relates to methods of transferring energy in a fluidenvironment in a treatment zone by carefully controlling the enthalpy ofthe incoming fluid environment and the enthalpy useful in the reduction,melting, heat treating, welding, cold treating, casting, surfacetreating and the like of metallic and nonmetallic bodies by whichadvantageous properties in the bodies are obtained.

More particularly, the present invention relates to a method of treatingmetals and nonmetals in a furnace in the presence of a fluidenvironment, as hereinafter set forth, under very exact controlconditions in the furnace obtained by controlling the enthalpy of theincoming fluid environment, for example, the temperature and pressure ofthe fluid environment before its entrance into the treatment zone of thefurnace and by controlling the enthalpy of the exhausting fluidenvironment, for example, the temperature, or energy level, of theenvironment as it exhausts from the treatment zone of the furnacethereby controlling the energy released by the environment in thetreatment zone which is thus available to control the reactions with themetallic and nonmetallic bodies being treated at the treatmenttemperature thereby imparting desired properties to the metals andnonmetals being treated. The furnace atmosphere or environment may be agenerated fluid mixture composed of liquid water saturated with a majoramount of carbon dioxide, a minor amount of methane (which can beomitted), and lesser amounts of hydrogen and carbon monoxide while inthe temperature range of from about 32F to about F and while maintainingthe solute gases under atmospheric pressures up to the critical pressureof water, which is 218.5 atmospheres. This generated saturated fluidmixture may be in equilibrium or neutral, may be oxidizing anddecarburizing, may be oxidizing and carburizing, may be reducing andcarburizing, or may be reducing and decarburizing by controlling thetemperatures and pressures within the range mentioned during itsgeneration. Also, the furnace atmosphere may be inert gases, such asargon and helium, or may be a reducing gas, such as hydrogen, or may bea nitriding gas, such as nitrogen, or carburizing gases, such as methaneor controlled fluid mixtures, such as endother mic or exothermicenvironments.

The metals which may advantageously be treated with the method includeall of the elements of the Periodic Table. The nonmetals include theoxides, sulfides, sulphates, silicates, phosphates, and carbonates ofthe elements of the Periodic Table.

It is therefore an object of the present invention to treat metals andnonmetals under very exact control conditions in the furnace bycontrolling the enthalpy of the gaseous environment just prior toentering the treatment zone and by controlling its enthalpy as itexhausts from the treatment zone.

A further object of the present invention is to treat metals andnonmetals in a gaseous environment composed of liquid water saturatedwith a high or major concentration of carbon dioxide, with or without aminor amount of methane and lesser amounts of hydrogen and carbonmonixide to impart desired properties to the metals and nonmetals.

A further object of the present invention is the provision of animproved method of heat treating and cold treating of metallic andnonmetallic bodies in which the constituents of the furnace atmosphereat any given temperature are balanced out thereby establishing anequilibrium between the gases in the atmosphere and the composition ofthe bodies in the furnace and which balance is maintained as the furnacetemperature changes.

A still further object of the present invention is the provision of animproved method of heat treating and cold treating metallic andnonmetallic bodies by balancing the furnace atmosphere to the body inthe furnace and automatically maintaining this balance at all times asthe furnace temperature changes.

Yet a further object of the present invention is the provision of animproved method of treating metallic and nonmetallic bodies by which newand unusual structures having highly advantageous properties areobtained in comparison to those obtained by present commercialtreatments.

A still further object of the present invention is the provision of amethod of treating metallic and nonmetallic bodies in a balancedatmosphere by which new and improved properties are imparted to thebodies.

. Yet a further object of the present invention is the provision of animproved method for processing metallic and nonmetallic bodies, such asannealing, normalizing, hardening, tempering, carburizing, nitriding,surface coating, freezing and the like by which improved results areobtained.

A further object of the present invention is the provision of a methodin which metallic and nonmetallic materials are treated in an atmospherewhich has the characteristics or properties of being in equilibrium orneutral, oxidizing and decarburizing, oxidizing and carburizing,reducing and carburizing, or reducing and decarburizing.

A further object of the present invention is to control closely therelease of heat energy or reaction energy or both within the treatmentZone to obtain a desired heat balance for the bodies being treated.

It is a further object to control the energy balance in a treatment zonewhile treating metallic and nonmetallic materials by controlling theenthalpy of the environment during generation, prior to its entranceinto the treatment zone, and finally as it exits from the treatment zonethereby controlling the heat energy or reaction energy released in thetreatment zone at the treatment temperature (difference between theenergy entering the treatment zone and the energy leaving the treatmentzone) thereby imparting desirable properties to metallic or nonmetallicbodies. In this connection, for most metallic and nonmetallic bodiesextremely close enthalpy control is desired, of the order of a fewb.t.u.s per cubic foot.

A still further object of the present invention is the provision of amethod of treating metallic and nonmetallic bodies in which theenvironment is preheated to a controlled heat content or enthalpy justprior to its use as a treating environment to provide an environmentwith an energy level equal to or higher than the energy level existingduring treatment and in which the heat content or enthalpy of theenvironment is controlled on its exit from treatment thereby controllingthe energy released by the environment surrounding the metallic andnonmetallic bodies during treatment by which advantageous properties areimparted to them.

A still further object of the present invention is the provision of animproved method of processing metallic and nonmetallic bodies by closelycontrolling the heat or reaction energy or both released to or by theenvironment to structures having highly advantageous properties areobtained in comparison to those obtained by methods of the prior art.

Other and further objects, advantages and features of the invention willbe apparent from the following description of presently preferredembodiments of the invention, given for the purpose of disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation view, partly insection, illustrating a retort furnace useful in the invention fortreating metallic and nonmetallic bodies;

FIG. 2 is a sectional view of an exhaust pipe to an environment of lessthan one atmosphere, such as found when a partial pressure is pulled onthe exhaust, and containing an energy level sensing element, here shownas a thermocouple;

FIG. 3 is a sectional view similar to that of FIG. 2 illustrating anexhaust pipe from a treating zone to an environment of one atmosphere ofpressure with a counter weight flapper valve, which may be omitted forsome reactions, and an energy level sensing element;

FIG. 4 is a sectional view, similar to FIGS. 2 and 3, of an exhaust pipefrom a treatment zone where control is maintained at a pressure higherthan one atmosphere by a pressure control mechanism, here shown as abutterfly valve connected to a pressure control motor and an energylevel sensing element controlling at an elevated pressure;

FIG. 5 is an elevational view, partly in section, of a back pressurerelief valve which operates at th temperature of a treatment zone andreleases the treating environment into the treatment zone only when apreset pressure level is reached;

FIG. 6 is an elevational view, partly in section, of a treating furnace,containing a treating chamber or zone connected to a cooling orquenching chamber or zone with an exhaust pipe between the treating andcooling chambers containing the energy level sensing element, such asillustrated in FIGS. 2-4, inclusive;

FIG. 7 is a graph presenting the absolute heat contents at oneatmosphere of pressure of gaseous components of the staurated fluidmixture, the heat content of staurated water vapor, and the heatcontents of argon and nitrogen;

FIG. 8 is a schematic energy flow diagram for the saturated fluidmixture representing the energy flowing with preset conditions at thegenerator, preheater and ambient atmospheric pressures within thetreating chamber and with changeable conditions of furnace controltemperature and exhaust control temperature.

As previously mentioned, FIGS. 1, 2, 3, 4, 5 and 6 illustrate apparatussuitable for use in the method of the invention. It will be understood,however, that other apparatus may be used.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the art, previous effortshave not been directed to controlling the transfer of energy between theenvironment and the material being treated by carefully controlling theenthalpy of the environment before entry into the treatment zone andcontrolling the enthalpy of the environment exhausting from thetreatment zone to impart desired properties to the material beingtreated.

Also, in the art, previous efforts have been directed to the eliminationof the oxidizing gaseous constituents, such as carbon dioxide and water,in atmospheres for processing material at elevated temperatures.Surprisingly, however, a treatment environment having a high watercontent is extremely beneficial in treatment of metallic and nonmetallicbodies if the environment contains water balancing gases, carbondioxide, carbon monoxide, hydrogen and methane while kept under veryclose control.

It has further been found that liquid water will act as a carburetor toabsorb finite amounts of the water balancing gases to reach anequilibrium depending on the temperature and pressure of the solutewater balancing gases over the water as explained in my co-pending Pat.Ser. No. 719,613. The reactions are according to the following water-gasreactions:

The generated fluid mixture therefore constitutes liquid water balancedwith the water balancing gases carbon dioxide, carbon monoxide, hydrogenand methane. The generated fluid mixture may have the characteristics orproperties, depending on the temperature and pressure, of being inequilibrium or neutral, oxidizing and decarburizing, oxidizing andcarburizing, reducing and carburizing, or reducing and decarburizing.

The generated fluid mixture, on leaving the generator, has a presetenthalpy characteristic with known properties, but which must becontrolled throughout the process as the enthalpy requirement (heat) ofequations (1) and (2) changes drastically with any change in temperatureof the fluid mixture.

In one aspect of the process of the present invention, the enthalpy ofthe saturated fluid mixture is controlled by preheating under closelycontrolled temperature and pressure conditions, the metallic andnonmetallic materials are treated with the saturated fluid mixture in atreating chamber zone, and the enthalpy of the saturated fluid mixtureor a portion thereof exhausting from the chamber or zone is closelycontrolled.

All materials, both metallic and nonmetallic, have a definite and finiteenergy requirement for each particular temperature level. Static heatenergy from a heating furnace is not sufficient by itself to controlthese definite and finite energy requirements of metallic andnonmetallic bodies being treated. The heat content or enthalpy of theenvironment surrounding these materials during their treatment at anytreatment temperature has a pronounced effect on their final properties.In the present method these energy requirements are provided andcontrolled.

To provide and control such environmental energy during treatment in thetreating chamber an environment, which may be a fluid or fluid mixture,of known and predictable response to heating and cooling must begenerated or provided, such as those illustrated in FIG. 7 to whichreference is now made. The inert fluid argon is shown to have the lowestabsolute heat content at all temperatures and will follow curve Argon onheating and cooling at l atmosphere pressure. The nitriding gas nitrogenis shown to have the next highest absolute heat content and will followthe curve marked Nitrogen on heating and cooling at 1 atmospherepressure. The water-gas fluid mixture is shown to have the highestabsolute heat content and will follow the curve marked superheatedWater-Gas" on heating and coling at one atmospheric pressure. The liquidwater will follow the curve marked liquid out to a maximum ofapproximately 100,000 Btu/cf at 40F (not shown on graph) and droppingback to join the curve marked Saturated Water Vapor at the criticaltemperature of water 705.5F at 1 atmosphere pressure 14.697 psia). Toincrease the heat content of each of these gases it is necessary toincrease the pressure. For

instance, to increase the heat content of argon at 400F from 10 Btu/cfto 20 Btu/cf it is necessary to increase the pressure to 2 atmospheresor 29.394 psia. To increase the heat of the superheated Water-Gas at1,700F from 22 Btu/cf to 61.5 Btu/cf it is necessary to increase thepressure to 2.8 atmospheres or 41.15 psia.

Reference is now made to FIG. 8 in which is illustrated schematic energyflow balance curve for the method of this invention using the fluidmixture watergas as an environment. The fluid mixture here is shown tobe generated at a temperature of l20F and at a pressure of 41 l 5 psia;leaves the generator under control of flow control valve (14 in FIG. 1,114 in FIG. 6) into the preheater 16 in FIG. 1, 116 in FIG. 6) andfollows the curve C-D up to the critical temperature of water (705.5F)where it will have a heat content of 82.25 Btu/cf at 1 atmosphere ofpressure. If the furnace is being controlled at 1,700F and the backpressure relief valve 18 on the preheater shown in FIG. 5 is set to hold41 psia pressure the fluid mixture will follow curve D-N-M to l,700F. Ifthe back pressure relief valve is set to hold 1 atmosphere of pressurethe fluid mixture will follow curve D-F-S up to 1,700F. If the furnaceis being controlled at 1,000F. the fluid mixture will follow curve D-Nto 1,000F, and D-E-R to 1,000F, respectively. Thus a controlled heatcontent fluid or fluid mixture can be generated and supplied to thetreating chamber.

Curve AZl-Il(R-SB is the superheated Watergas curve on FIG. 7 andrepresents the heat content of the fluid mixture on heating and coolingat l atmosphere pressure. With the furnace being controlled at 1,700Fand the treating chamber at 1 atmosphere of pressure the fluid mixtureon cooling would follow that portion of the curve SRl(HZ. If the flow ofthe fluid mixture was increased to raise the temperature at the exhaustto H the rapid cooling from H to I would pull a partial pressure at theexhaust equivalent to I-T at l temperature level. If the flow of thefluid mixture was further increased to raise the exhaust temperature toK a greater partial pressure would be pulled on the exhaust equivalentto L-U at L temperature level. Thus, when the exhaust is controlled at Ka greater quantity of energy would be released in the treating chamberthan if the exhaust was controlled at H. Therefore, by the control ofthe energy entering the treating chamber through the preheater and bythe exhaust control to control the energy leaving the treating chamber,control of the energy released in the treated chamber is obtained at anyfurnace temperature level.

This released energy is reactive energy capable of shifting equations(1) and (2) from an equilibrium or neutral state to one which isoxidizing and decarburizing, oxidizing and carburizing, reducing andcarburizing, or reducing and decarburizing. Any of these combinationscan be obtained and controlled by the methods and apparatus of thisinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In one aspect of the inventiona saturated fluid mixture is generated which comprises liquid watersaturated with a major amount of carbon dioxide, a minor amount ofmethane and lesser amounts of hydrogen and carbon monoxide. Othercomponents may be present. This is accomplished by saturating liquidwater, while it is maintained at a temperature of from about 32F toabout 160F while the gases are maintained from atmospheric pressure upto the critical or equilibrium pressure of water. The carbon dioxide ofthe liquid water may comprise the largest pure component percentage byvolume of the generated fluid mixture. The generated fluid mixturecomposition has relatively low or minor amounts of hydrogen and carbonmonoxide. Methane is present in minor amounts; although, there is moremethane present than either hydrogen or carbon monoxide. If desired, themethane may be omitted The methods of the invention for preparing thesaturated fluid mixture of the invention comprise saturating liquidwater while maintaining it in the temperature range'of about 32F toabout 160F and under pressures up to the equilibrium pressure of water,which is 218.5 atmospheres. A preferred temperature of the liquid wateris within the range from 105F to l40F with a constant pressure of thegases in the range of 25 to 80 psia. Particularly good results have beenobtained by maintaining the liquid water at a temperature of the orderof about lF with a constant gas pressure of the order of about 28 to 60psia.

The gases which may be used to saturate the liquid water may be anycombination of oxidizing and reducing or oxidizing and carburizing gaseswhich will react to form in liquid water, within the temperature andpressure ranges specified, a high saturation of the water with carbondioxide with a minor amount of methane, and with lesser amounts ofhydrogen and carbon monoxide. Suitable gases for this purpose aremixtures of carbon dioxide and hydrogen or carbon dioxide and methane,or methane andoxygen, with or without combustion, which are presentlypreferred. If desired, additional carbon may be provided to the water inthe form of charcoal, coke, graphite and the like for the purposes ofstabilizing the oxidizing properties of carbon dioxide and water and thereducing and carburizing properties of methane. This additional carbonmaybe omitted. By controlling temperatures and pressures within theranges set forth liquid water saturated with these gases is produced,which may be in equilibrium or neutral, may be oxidizing anddecarburizing, may be oxidizing and carburizing or may be reducing anddecarburizing. It is essential, however, that the saturated fluidmixture generated by the process be maintained in essentially itsgenerated condition and transported to a treatment zone for treatment ofmetallic and nonmetallic materials in order to obtain the beneficialresult of the present invention.

The metallic bodies subject to treatment by the generated saturatedfluid mixture include all of the elements of the Periodic Table andtheir alloys, for example, steel, stainless steel, tungsten, molybdenum.vanadium and the like. The nonmctallic materials include the oxides,sulfides, sulphates, silicates, phosphates and carbonates of theelements of the Periodic Table.

By controlling the temperature and pressure the properties orcharacteristics of the generated saturated fluid mixture are controlled.For example, if the temperature of the liquid water is maintained at 50Fand the pressure of the gases is maintained at 10 psia, the generatedsaturated fluid mixture would have oxidizing and decarburizingproperties. If the temperature of the liquid water were raised to F,then the characteristics and properties of the generated saturated fluidmixture would be oxidizing and carburizing.

If the temperature of the water were maintained at F and the gases at apressure of 45 psia, then the generated saturated fluid mixture wouldhave the properties of reducing and carburizing. If the temperature ofthe water is reduced to 90F and the gases held at a pressure of 45 psia,the generated saturated fluid mixture would have the properties ofreducing and decarburizing.

In practicing the methods of the invention, the gases may be flowedunder controlled pressure into a chamber into intimate contact withliquid water in the chamber maintained from 32F to F with a gas headabove the upper level of the water maintained at a pressure up to theequilibrium or critical pressure of liquid water, which is 218.5atmospheres. When the gases cease to flow into the chamber, the liquidwater is saturated and this may be used as an indication of suchsaturation. A saturated fluid mixture according to the invention hasthus been formed and may then be discharged from the chamber, care beingtaken to maintain the properties and characteristics of the formedsaturated fluid mixture on discharge from the chamber and transfer to atreating zone of chamber.

The following tables illustrate generated saturated fluid mixtures inwhich liquid water is saturated at the temperatures and pressures setforth with carbon dioxide, carbon monoxide, hydrogen and methane whichwere provided by mixtures of carbon dioxide and hydrogen, mixtures ofcarbon dioxide and methane, and mixtures of methane and oxygen, with andwithout combustion. These tables indicate the percentage of the purecomponents by volume saturating the water at the temperatures andpressures indicated.

TABLE I The temperature of the water was maintained at 41F and aconstant pressure of the gases was maintained at 19.2 psia. Thesaturated fluid mixture had the following composition.

PURE COMPONENT PERCENTAGE BY VOLUME CO; 62.58% CO l.38% H 90% CH 2.] 1%H 0 33.03% Total: 100.00

This saturated fluid mixture was reducing and decarburizing.

TABLE II The temperature of the water was maintained at 41F but thepressure was increased to 44 psia. The saturated fluid mixture had thefollowing composition.

PURE COMPONENT PERCENTAGE BY VOLUME co 76.92% co 1.70% H, i.|% CH 2.60%m0 l7.68%

Total: 100.00

This saturated fluid mixture was reducing and decar burizing.

TABLE III The temperature of te liquid water was maintained at 122F butthe gas pressure was decreased to 19.2 psia. The saturated fluid mixturehad the following composition.

PURE COMPONENT PERCENTAGE BY VOLUME CO 38.36% CO 1.42% H 1.41% CH, 1.88%H 0 56.93%

Total: 100.00

psia. The generated saturated fluid mixture had the followingcomposition.

PURE COMPONENT PERCENTAGE BY VOLUME co 56.53% co 2.09% H2 2.08% ca.2.77% E 0 36.53% Total: 100.00

This saturated fluid mixture was reducing and slightly carburizing.

TABLE V The temperature of the water was maintained at 41F and thepressure was raised to the pressure of 218.5 atmospheres. The generatedsaturated fluid mixture had the following composition.

PURE COMPONENT PERCENTAGE BY VOLUME C 2 93.16% CO 2.06% H 1.34% CH,3.14% H=tl 30% total: 100.00

This saturated fluid mixture was reducing and decarburizing.

TABLE VI The pressure of the gas was maintained at 218.5 atmospheres andthe temperature of the water was raised to and maintained at 122F. Thisresulted in a saturated fluid mixture having the following composition.

PURE COMPONENT PERCENTAGE BY VOLUME 2 88.36% CO 3.27% H, 3.26% CH. 4.32%H 0 .79% total: I00.00

This saturated fluid mixture was reducing and decarburizing.

TABLE VII The following is a typical composition generated by aconventional endothermic generator in the art today.

PURE COMPONENT PERCENTAGE BY VOLUME C0 0.40% CO 19.60% H, 40.00% CH,.02% H 0 .8770 (dew point 43F) N, 38.93% total: 100.00

It can be seen from the composition of this fluid mixture that it isvery low in the water and water-forming consituents, carbon dioxide andmethane. The composition is mainly carbon monoxide, hydrogen andnitrogen, which is strongly carburizing and decarburizing and notneutral, and which provides a very stable atmosphere which changes verylittle in pressure during changes in temperature and thus is not inequilibrium.

Referring now to FIG. 1 a heating furnace containing a retort for atreating chamber is illustrated. The heating furnace may be anyconventional furnace, any type of shape and design. For example, theretort may be eliminated and gas heating means used in place of theelectric heating means shown if provision is made for proper venting ofexcess combustion heating gases. As illustrated the furnace includes anouter shell 2 with insulation 4 and an inner shell 6 with any type ofheating means, here shown to be electric with heating elements 8connected by leads 10 to relays, not shown, common in the art tocontroller 42, actuated from thermocouple 38 through leads 40, whichcontrols the temperature of retort 11 containing the metallic ornonmetallic bodies being treated (not shown) in treating Zone 12. Thesaturated fluid mixture from a generator (not shown) or other fluidenvironment from a suitable source, not shown, enters through aproportional flow control valve M actuated by a proportional flowmechanism 26 common in the art, through a pipe 15 to preheater l6 whichmay be a single pipe, 2; series of pipes, straight or coiled, andconnected to a back pressure control mechanism 318, which is open to thetreating chamber 12 containing the bodies to be treated. The fluid orfluid mixture in the preheater may be heated to the temperature of thetreating chamber 12 and at a controlled pressure from the pressureambient within the treating chamber to a pressure equal to the criticalpressure of water (218.5 atmospheres), as determined by the controlledsetting on the back pressure regulator 18. When the saturated fluidmixture is at the controlled temperature and pressure (controlledenthalpy) it is expelled into the treating chamber 12 containing themetallic or nonmetallic bodies or parts to be treated, and out throughexhaust pipe opening 2T through an exhaust pipe 36 containing a sensingdevice 34 to sense the enthalpy of the exhausting fluid or fluid mixtureat point 34 in exhausting from the treating chamber. The enthalpy at 34depends primarily on the internal energy, the volume and the pressure ofthe fluid or saturated fluid mixture at that point. Therefore, bycontrolling the flow of fluid or saturated fluid mixture at M a controlof the enthalpy at 34 is obtained.

Now referring to FIG. 2, there is shown a section of the exhaust pipe towhich the letter A has been added to like parts for convenience ofreference. The exhaust pipe 36A contains the enthalpy sensing device34A, here shown as a thermocouple, and is exhausting the fluid or fluidmixture to an environment of less than 1 atmosphere pressure; Thus, theenthalpy at 34A is being controlled at a partial pressure.

In FIG. 3 is shown a section of the exhaust pipe here give the letter Bfor like parts. The exhaust pipe 36B contains the enthalpy sensingdevice 34B and the counter weight flapper valve 44 to control theenthalpy at 1 atmosphere pressure at 34B.

FIG. 4 shows another modification of the exhaust pipe where the letter Chas been added for like partsv Here the exhaust pipe 36C contains anenthalpy sensing device 34C operating at a pressure higher than 1atmosphere controlled by the butterfly valve 46 through a pressurecontrol mechanism 48 common in the art. Thus, the enthalpy level isbeing controlled at a higher pressure than 1 atmosphere.

FIG. illustrates one means of a back pressure regulator designated as 18in FIG. 1 and 118 in FIG. 6. This regulator operates at the temperatureof the treating chamber to permit the fluid or fluid mixture to leavethe preheater 16 (116 in FIG. 6) when the fluid or fluid mixture hasreached the pressure set by a controlled weight pressing down on acontrolled dimensioned area. The preheated fluid or fluid mixture from16 (or 116 in FIG. 6) enters an opening 60 closed with a plug 56 havingan orifice 58 of controlled dimension with a weight 52 pressing down onthe orifice area 58, here shown as ball 52. This weight 52 may be of anyshape or configuration. The known and controlled weight 52 pressing on aknown and controlled orifice area 58 builds up a known and controlledpressure at 60. As the fluid or fluid mixture reaches the temperature ofthe treating chamber and at a pressure set by the weight 52 and orifice58 combination it expels out into the treating chamber through openings54 at a controlled enthalpy level.

In FIG. 6, to which reference is now made, is shown an elevational view,partly in section, of a treating furnace connected to a cooling orquenching chamber 170 by an exhaust pipe 136 and a closable door 172.The saturated fluid mixture from a generator (not shown) or other fluidenvironment from a suitable source or sources, not shown, enters througha flow control valve 114 and a pipe 115 into the preheater 116 locatedin the heated zone 112 of the furnace 102 and is expelled out throughback pressure regulator 118 into the treating zone 112 of the furnace. Afumace thermocouple 138 controls the furnace temperature through leads140 to a temperature controller 142 which actuates a heating meanscommon in the art and not shown in the drawing. The fluid or fluidmixture in being expelled from the back pressure regulator 118circulates in the treating zone 112 and flows out exhaust opening 120through an exhaust pipe 136 in which is located an enthalpy sensingelement 134, such as a thermocouple connected through leads 132 to atemperature controller 130 which actuates the proportional flow controlvalve 114. The fluid or fluid mixture on leaving the exhaust pipe 136 at135 enters the cooling or quenching chamber 170. A blower fan 168 drivenby a the motor 164 pulls a partial pressure at the exhaust 135 andpushes the hot fluid or fluid mixture down toward the cooling water 188which cools and thereby contracts its volume and moves out under abaffle 189 to an overflow 198 to a drain or re-circulating system, notshown. The gases not absorbed pass out through a vent 196. Theproportional flow of the fluid or fluid mixture is controlled by theenthalpy at 134 controlled through the flow control valve 114 in theinlet pipe 101. The temperature of the cooling water 188 may beregulated by a control valve 186 to hold approximately F. A temperaturecontrol mechanism, common in the art, and not shown, may be utilized tooperate a control valve 186 to hold a constant temperature of thecooling water 188. A spray pipe 182 is equipped with the nozzzles 183 tospray quench the hot parts 184 if so desired by opening the coolantvalve 180.

With the furnace being controlled at a desired temperature and the flowof fluid or fluid mixture through the flow control valve 114 beingcontrolled by the exhaust controlled thermocouple 134 to hold a constanttemperature in the range of 250F to 1,500F a desired energy balance flowis established according to FIG. 8, and the metallic materials are readyto be treated in the new and unique environment of this invention. Theparts are loaded on suitable trays or baskets 192 resting on a rollerconveyor 194, or any other suitable means of conveyances. The coolingchamber door 190 is raised, or a water spray curtain may replace door190, and the work load 192 is pushed into chamber 170 onto hearth 178attahced to an elevator 179, here shown to have a double hearth, but asingle hearth may be used. The furnace door 172 is raised, and work ispushed to 162 through the opened door 172 which is then closed. Ifelevator 79 has a double hearth, as shown, a second work load 192 can berolled on hearth 178 and elevator 179 raised by any convenient means176. The upper hearth with its load is in the hot part of the coolingchamber and is being preheated, while the lower hearth 178 is empty. Thefurnace control 142 is maintaining a constant temperature in thetreating chamber 112, and the exhaust control 134 controls the releaseof the reactive energy from the environment. After a given processingtime, the door 172 is raised and the hot work 162 is pulled to the lowerhearth 176 of the elevator 179 and the elevator 179 is lowered to itscooling position, while the preheated work on the upper hearth 178 ofelevator 179 is pushed to 162 in the treating chamber and the door 172is closed. The cooling chamber door is then raised and another work load192 is pushed onto the upper hearth 178 of the elevator 179, and thecooling chamber door 190 is again closed. After the work on the lowerhearth 178 is cooled the elevator 179 is raised and the cooled processedwork is pulled from the furnace back to 192 and down the processed line,not shown. The cycles may be repeated in production Runs.

No details have been given of the various controllers, thermocouples,valves and the like as these are all conventional and are readilyavailable.

The following examples are illustrative of the beneficial effect oftreating metals and non-metals with the saturated fluid mixture andother fluids according to the invention.

EXAMPLE I In this example parts made of NE. 8620, a carburizing grade ofsteel, was treated in a furnace similar to FIG. 6 following the energyflow curve of FIG. 8. The liquid water in the generator was saturatedwith a mixture of carbon dioxide and methane gas at a pressure of 41.5psia and controlled at a temperature of 120F. The back pressureregulator 118 was set to hold a pressure of 33.5 psia on the preheater.The low control valve 126 was manually operated and was set to providean exhaust temperature of 840F at 134. The cooling water was manuallycontrolled to hold a temperature of 90F. The furnace temperature was1,700F.

The parts carburized under these conditions showed a carbon content of0.96 percent and with a case of depth of 0.080 inches. Examination ofthe carburized cases indicated the structures were fine grain,completely free F free carbides, and retained austenite. The overallstructures was more dense and finer grained as compared to partscarburized in a conventional manner. Testing the parts in a laboratorybearing testing machine showed the wearing surfaces to hold up l618hours with 0.010 to 0.020 inches wear before final failure of thecarburized surface. Other of the same parts when given the sametreatment in the presence of a conventional endothermic type ofatmosphere held up only 12-i4 hours with 0.010 to 0.020 inches wearbefore final failure of the carburized surfaces.

EXAMPLE II in this example a study was made of the affect of thesaturated fluid mixture on the nonmetallic inclusions contained within acommercial grade of S.A.E. 1040 steel. Examination of steel prior to thetest indicated the nonmetallic inclusions were of the oxide and silicatetype with ratings of approximately No. 3 to No. 4 on the A.S.T.M. ratingchart. After treatment in the saturated fluid mixture with the exhaustbeing controlled at a temperature of 730F and with other conditions asdescribed in Example I there was a reduction of these non-metallicinclusions bringing the A.S.T.M. ratings up to No. l to 2v The samesteel when given the same treatment in the presence of the conventionalendothermic type of atmosphere showed no change in the size, shape ornumber of nonmetallic inclusions.

EXAMPLE ill in this example a study was made of the effect of theexhaust temperature control on the treatment of metal lie andnonmetallic bodies. The fluid, argon, was used for an environmentbecause it is inert and will not react with the parts being treated. Anyreactions found in the metallic or nonmetallic bodies would be due tothe enthalpy of the environment as controlled by the preheater and theexhaust control. The samples were made from a medium carbon steel, knownin the trade as Doac.

A retort furnace similar to that shown in FIG. l with the preheater 16but without the back pressure regulator B8, was connected at 1 to anargon cylinder carrying l50 psig pressure through regulators common inthe art to deliver a constant pressure of 20 psig at 14. The flow of theargon through the valve 14 was manual and the exhaust temperature sensedby thermocouple 34 was recorded on a chart on the recorder 30.

With the retort l2 being controlled at l,600F by thermocouple 38 throughcontroller 42, the inert gas argon was fed through valve 114 into thetreating chamber 12 and out through the exhaust opening 211, the exhaustpipe 36 containing the thermocouple 34 and recording on recorder 30, theexhaust pipe 36 being connected through a flexible pipe to a hosemaintained under water to give a constant back pressure of 2 ounces/sq.inch gage (2.0 psig), not shown. With the argon flow being manuallycontrolled to record an ex haust temperature of 200F on the recorder 30by the flow of 18 cubic feet of argon per hour the D6ac steel was heldat temperature for 1 hour time. Thereafter, the retort 11 was allowed tocool with the argon still flowing. As the treating chamber 112 cooledthe flow of argon had to be increased to hold the exhaust temperature 34at 200F. For instance the retort 12 at l,400F requirPd a flow of 20 cfh,at l,200F required 25 cfh, and at ll000F required a flow of 30 cfh. Whenthe retort was cooled to room temperature the lid 22 was removed byloosening the nuts 20 and the D6ac parts examined by a hardenss checkand microscopic studies. Under the microscope the surface showed anonmentallic oxide layer of scale, with an undernPath layer ofdecarburized metal to a depth of 0.008. The evidence was clear that toolow an enthalpy had been maintained by the exhaust being controlled at200F and the preheater operating at the retort l2 pressure, to preventthe metallic material changing to the lower heat balance nonmetallicoxide of the pure elements.

EXAMPLE IV In this example the exhaust temperature control was raised to600F with all other conditions as described in Example III. In this testwith the treating chamber 12 at 1,600F the flow of argon was 55 cfh tomaintain an exhaust temperature of 600F. As the treating chamber cooledthe flow of argon was changed to hold the 600F exhaust temperature asfollows: at 1,400F the required flow of argon was 62 cfh to hold the600F exhaust temperature, at 1,200F the flow had to be increased to 74cfh, while at l,OO0F the flow was further increased to 9l cfh to holdthe 600F exhaust temperature.

On examination the B6210 was completely free of any non-metallic oxideand any decarburizationNo carburization was present because unlike thesaturated fluid mixture of this invention argon cannot carburize. Theenthalpy of the environment surrounding the work in the treating chamberhad been maintained at a good level for the medium carbon D6ac steel.

EXAMPLE V In this example the exhaust temperature control was raisedfurther to 1,000F with all other conditions as described in Example lll.With the treating zone 12 controlled at a temperature of 1,600F the flowof argon had to be 92 cfh to obtain an exhaust temperature of 1,000F. Asthe treating chamber 32 was cooled the argon flow had to be increased asfollows: treating zone 12 at 1,400F the argon flow had to be increasedto cfh, at 1,200F the required argon flow was 124 cfh, at l,O00F theargon flow had to be l52 cfh.

On examination the Doac steel was free of any nonmetallic oxides but hasa very serious decarburized surface with evidence that the internalstructure had an imbalance of energy; Very fine grinding of the samplewould start an exothermic release of this imbalance in energy and thespecimen would get very hot. This is evidence that the enthalpy controlof the environment surrounding work being treated by the control of theexhaust temperature is of paramount importance in the processing ofmetallic and nonmetallic bodies.

EXAMPLE Vl In this example a saturated fluid mixture was used. The gasesused in saturating the liquid water were air from a central aircompressor storage at about 120 psia combined with a synthetic mixtureof hydrocarbon gases composed mainly of methane and propane.

Both the air and the hydrocarbon gases had their pressures adjusted andbalanced to apply a head pressure of 44psia. The saturated fluid mixtureflowed through the flow controlled valve 14 (FIG. 1) into the preheater11 and into the treating zone 12 and out through the exhaust 21 in whichwas placed the thermocouple 34 to measure the heat content, or theenergy level of the generated environment. With the furnace controlledat a temperature of 1,550F and showing an exhaust temperature of 425Fthe following samples were tested:

1. Shim stock 0.010 thick -for carbon potential determinations.

2. Pure iron with less than 0.02 percent contained carbon 3. S.A.E. 1018a low carbon steel 4. S.A.E. 4340 a medium carbon, high alloy steel 5.S.A.E. 52100 a high carbon tool steel.

The samples were run for 2 hours in the furnace and pulled with tongsand water quenched. The results of the tests on these samples showed thefluid mixture under the above conditions to be reducing and withcontrolled carburizing/decarburizing potential of 0.60 percent carbon.

EXAMPLE VII In this example, vanadium oxide ore containing 41.98 percentoxygen was run in the manner explained in Example VI with the exceptionthat the time in the furnace was for 12 hours. In this treatment thenonmetallic ore was reduced by approximately 98.0 percent of thecontained oxygen. The sample was found to be clean and free of all soot.

The same nonmetallic ore run in the same manner in presence of theconventional endothermic type of atmosphere was found to have beenreduced only 24.6 percent and with a pick-up of carbon soot.

EXAMPLE VIII In this example pure tungsten powder of 99.98 percentpurity was converted to tungsten carbide when treated in a furnace inthe presence of a saturated fluid mixture. The powder was exposed for aperiod of 18 hours to the furnace temperature controlled at 1,880F. Thesaturated fluid mixture was generated in a generator, not shown. In thisexample, the gas used in saturating the liquid water was carbon dioxideand methane. The saturated fluid mixture, under control of the rate offlow, moved to the preheat coil 11 located in the treating zone 12 ofthe furnace, into the treating zone 12 of the furnace, and out theexhaust 21 in which waslocated the thermocouple 34 to measure the heatcontent or energy level of the exhausting gases. With the exhaustrunning at 840F the gaseous mixture had a heat content of 50 Btu/cf.

Examination of the treated tungsten powder showed the material to befree of soot, and on analysis showed the tungsten to have been convertedto a tungsten carbide containingg 1.78 percent carbon.

The same tungsten run in the same manner in the presence of theconventional endothermic type of atmosphere was found to be sooted upwithout the formation of any tungsten carbide.

6O TemPerature at EXAMPLE IX In this example, iron oxide ore containing29.6 percent oxygen and ground to a particle size of 30 to 80 mesh wastreated in a furnace controlled at a temperature of 1,700F with theexhaust gases controlled at 600F in the presence of the eaturated fluidmixtute of Table IV. After the ground ore was exposed for a period of 12hours to the furnace temperature of 1,700F

in the presence of the saturated fluid mixture, the fur- An examinationof the furnace system showed no sooting with clean, reduced particles.Analysis of the particles indicated the oxygen content to be 1.3percent. The treatment of the iron ore oxide in the saturated fluidmixture had removed 95.8 percent of the oxygen in the iron oxide ore.

The same iron oxide ore was treated in the furnace under the sameconditions as previously indicated in the presence of the endothermictype atmosphere of Table VII. After the test runs, the furnace systemhad 25 a heavy soot deposit and the iron oxide ore contained 21.4percent oxygen, or a removal of only 27.7 percent of the oxygen from it.

The following tables illustrate the flow of argon and nitrogen to holdexhaust temperature as indicated.

TABLE VIII Argon flow, in cubic feet per hour 77F, required at 1 to holdexhaust temperature at 34 (or 134) when the treating zone 12 (or 112) iscontrolled as shown.

Nitrogen flow, in cubic feet per hour (77F) required at l to holdexhaust temperature at 34 (or 134) when the treating zone 12 (or 112) iscontrolled as shown.

Treating Zone Exhaust Temperature Control 34 (or 134) "F Nitrogen Flowat enerator to hold xhaust temperature at 34 (or 12 (or 112) "F Theforegoing examples are representative and similar results may beobtained when treating any of the elements of the Periodic Table andtheir alloys or their oxides, carbides, silicates, sulfides, sulphates,phosphates and carbonates.

EXAMPLE X In this example the effect of energy control of an environmentwas determined under the following conditions: an environment was usedsimilar to that shown in Table VII in which the gases of the water-gasreaction were saturated with water at approximately 43F; the counterbalance flapper 44 of FIG. 3 was removed from the exhaust 36b givingexhaust conditions similar to that of FIG. 2; and the back pressureweight 52 of the regulator of FIG. 5 was removed permitting operation ata pressure slightly higher than atmospheric.

A furnace similar to the one shown in FIG. 6 was used without thecooling chamber 170. The exhaust 1.36 was open to the atmosphere. A flowvalve, a mercury bulb temperature sensing device and controlleractuating the flow valve were used to control the exhaust temperature bythe control of the flow of gases into the treating chamber. The mercurytemperature sensing bulb 134 was placed in an offset in the exhaust 136in order to avoid any radiant heat from the treating chamber I12striking the sensing bulb 134. These devices are common and readilyavailable. For example, these devices were Partlow Model 60 Flow ControlValve, Partlow Indicator 194-1 O0/650F, with 665 BSP 220-10 Piston-Pak,with one-half inches -2lSST-l05.

Shim stock, 1 inches X 6 inches X 005 inches thick, containing 0.08percent carbon were used as specimens. The treating chamber 1 12 wascontrolled by separate instrumentation at a temperature of 1,5 50F.Duplicate shims, wired together, were placed in the treating chamber 112and held for 30 minute periods and were then water quenched in each ofthe following tests. Carbon analysis of both shims was made and theaverage of the two were found as follows:

Exhaust Temperature Control "F Carbon 3 50 0.079 3 65 0.078 3 70 0.041 380 0.036 390 0.0 l 7 400 0.269

EXAMPLE X] With the furnace and exhaust temperature control operating asdescribed in Example X, a nitriding test was run. The exhausttemperature control was set to hold a temperature of 390F at 134 in theexhaust. Ammonia, from a cylinder, was fed through a flowmeter into thefurnace. With the ammonia flowing at a rate of 25 cubic feet per hour,and the endothermic gas flow controlled at a rate to hold an exhausttemperature of 390F at 134 the shims were placed in the treating chamber1112, held for 30 minutes and water quenched.

On examination the shims had evidence of having been nitrided. They werefile hard, but could take some bending prior to breaking. The evidencewas clear that during the process of decarburization in the presence ofa nitriding gas a nitrided case was formed. It was further evident thatthis nitrided case had more ductility than the nitrided case common inthe art formed by prior processes.

The same test was run with the treating chamber 112 being controlled at1,040F instead of the l,550F. Here, again, the shims had evidence ofbeing nitrided. Thus, by controlling the exhaust in accordance with thisinvention, both alpha and gamma iron can be made to take a nitridedcase.

EXAMPLE XII In this example the effect of energy control of anenvironment was determined under the following conditions: theendothermic gas of Table VII was fed through the flow control valve 1114,126 of FIG. 6, but before entering' the treating chamber 112 thegases were made to flow through a water bath to saturate the gases ofthe water-gas reaction with water; the counter balance flapper 441 ofFIG. 3 was placed back on the exhaust; and the back pressure weight 52of the regulator of FIG. 5 was left out permitting operation at pressurejust slightly higher than atmospheric.

T he exhaust temperature control functioned in the same manner asdescribed in Example X. The temperature of the water bath started out atapproximately 60F, but with the exhaust 134 being controlled at 390F thewater bath stabilized out at approximately 120F. The heating of thewater bath occurred from-the backing up of heat from the treatingchamber 112 through the inlet pipe of FIG. 6.

With the counter balanced flapper 44 of FIG. 3 on the exhaust thereaction was forward and was again carburizing at the following exhausttemperatures:

Exhaust Temperature Control "F Carbon 350 0.237 360 0.338 370 0.602 3800.992 390 1.420 400 1.226

The evicence is clear that by controlling the energy of the exhaustingenvironment the thermodynamic energy of the environment is changed in acontrolled manner.

EXAMPLE XIII carbon and hydrogen, readily decomposes at temperaturesabove 1,020F. The carbon formed can either be graphitic or gaseousdepending on the enthalpy, or heat content, of the decomposition. Thehydrogen can be molecular and/or atomic.

The furnace used was similar to that shown in FIG. 1 with the followingimposed conditions: commercial available natural gas (methane) at 4 to 5psig was used as an environment after it was pressure boosted to 150psig by a gas booster pump, common in the art; the counter balanceflapper 44 of FIG. 3 was on the exhaust 36b; and the ball weight 52 ofFIG. 5 was replaced with a bar of steel, 1 inches diameter by 31.75inches long. This weight pressed down on an orifice 58 which was 0.250inches in diameter. This back pressure regulator 18 was designed topermut flow of the methane environment into the treatment zone 12 onlyafter a pressure of 144 psig had been reached in the preheater 16 at thetemperature of the treatment zone 12.

The nonmetallic material used as samples was the iron ore described inExample IX. It was used because a supply of this ore was readilyavailable and the processing of iron ore is of great economic importancein the metallurgical art. Any of the nonmetallic materials can beprocessed in the same manner of these examples, such as the oxides,sulfides, sulphates, silicates, phosphates and carbonates of theelements of the Periodic Table, as previously mentioned.

The treating chamber 12 was controlled at 1,700F by instrumentation 42,while the exhaust temperature 34 was controlled by a thermocoupleactuating a motorized L & N Control Valve through an L & NProportional-Controller. The temperature was set to control the exhaust34 at 360F by the control of the flow of the methane environment throughthe motorized control valve 14.

A handful of the nonmetallic iron ore was placed in a basket and loweredinto the treating chamber 12 and the lid rescaled on the chamber. In ashort period of time the flame 35 began to change color to a brightyellow indicating that a reaction with the nonmetallic oxide was takingplace.

After approximately 2 hours reaction time the basket with its sample wasremoved from the treating chamber 12 and was oil quenched to stop allreactions. The sample was then treated to remove all traces of oil fromthe particles prior to testing.

On visual examination the particles had taken on a bright, lustrousappearance entirely different from the dull black appearance of thenonmetallic oxide. On smashing the particles on an anvil with a hammerit was revealed that the particles were now malleable, bright metallicmaterial.

A chemical analysis of theparticles indicated that they had lost most ofthe oxide and now contained 0.26 percent carbon dissolved in thegammairon. Under the microscope no evidences of carbon as graphite couldbe seen.

Thus, the reaction was reducing and carburizing by preheating themethane environment and controlling the enthalpy of the methaneenvironment while exhausting.

When using envionments containing water, such as a saturated fluidmixture, best results are obtained by maintaining the exhausttemperature within the range of about 212F to about 1,500F, thepreferred ranges being from about 212F to about 400F for low waterconcentration mixtures and from about 400F to about 980F for higherwater concentration mixtures.

No more examples are set forth as by simple experimentation optimumconditions can be determined for various environments, the materialbeing treated and the results desired.

It is apparent from the foregoing that the present invention is wellsuited and adapted to attain the objects and ends and has the featuresand advantages mentioned as well as other inherent therein.

While presently-preferred embodiments and examples have been given forthe purpose of disclosure, many changes may be made therein and theinvention may be applied to many additional uses and materials to obtaindesired properties in various materials which are within the spirit ofthe invention as defined by the scope of the appended claims.

What is claimed is: l. A method of controlling the transfer of energy ina fluid environment in a treatment zone comprising,

flowing the fluid environment into the treatment zone; exhausting thefluid enivronment from the treatment zone, and

controlling the enthalpy of the fluid environment before flowing intothe treatment zone independently of the treatment zone.

2. The method of claim 1 including,

controlling the enthalpy of the fluid enviroment before flowing into thetreatment zone to produce a predetermined enthalpy in the fluidenvironment at least equal to that of the fluid environment exhaustingfrom the treatment zone.

3. The method of claim 1 including,

controlling the enthalpy of the fluid environment exhausting from thetreatment zone in response to its temperature.

4. The method of claim 3 including,

controlling the enthalpy in the fluid environment entering the treatmentzone to produce a predetermined enthalpy in the fluid environment beforeflowing into the treatment zone at least equal to that of the fluidenvironment exhausting from the treatment zone.

5. A method of altering the properties of materials in treatment zonecomprising,

flowing into the treatment zone and about the material a fluidenvironment selected from the group consisting of liquid water saturatedwith a major amount of carbon dioxide, a minor amount of methane, andlesser amounts of carbon monoxide and hydrogen, and liquid watersaturated with a major amount of carbon dioxide and lesser amounts ofcarbon monoxide and hydrogen, while maintaining the temperature of thewater from about 32F to about F and under pressure from ambientatmospheric to 218.5 atmospheres while flowing into the treatment zone,and exhausting the fluid environment from the treatment zone. v 6. Themethod of claim 5 including, controlling the temperature of the fluidenvironment exhausting from the treatment zone between about 212F andabout 1,500F in response to its temperature while exhausting. 7. Themethod of claim 5 including,

controlling the temperature of the fluid environment exhausting from thetreatment zone within the temperature range of about 212F to about 400Fin response to its temperature while exhausting.

8. The method of claim including,

controlling the temperature of the fluid enviornment exhausting from thetreatment zone within the temperature range of aboFt 400F tO about 980Fin response to its temPerature while exhausting.

9. The method of claim 6 including,

controlling the enthalpy in the fluid environment to produce apredetermined enthalpy therein before flowing into and independently ofthe treatment zone.

10. The method of claim 6 including,

controlling the enthalpy in the fluid environment to produce apredetermined enthalpy therein at least equal to that of the exhaustingfluid environment before flowing into and independently of the treatmentzone.

H. A method of treating material whose properties are altered therebycomprising,

generating a fluid environment selected from the group consisting ofliquid water saturated with a major amount of carbon dioxide, a minoramount of methane, and lesser amounts of carbon monoxide and hydrogen,and liquid water saturated with a major amount of carbon dioxide andlesser amounts of carbon monoxide and hydrogen while maintainingtemperature of the water from 32F to about 160F and under pressure fromatmospheric to 218.5 atmospheres,

flowing the generated fluid environment to a treatment zone whileretaining the properties of the generated saturated fluid,

introducing the generated fluid environment into the treatment zone andabout the material thereby providing a fluid environment about thematerial in the treatment zone during treatment, and

exhausting the fluid environment from the treatment zone.

12. The method of claim ll including,

controlling the temperature of the fluid environment exhausting from thetreatment zone within the temperature of from about 212F to about 1,500Fin response to its temperature while exhausting.

13. The method of claim 11 including,

controlling the temperature of the fluid environment exhausting from thetreatment zone within the temperature range of from about 2 l 2F toabout 400F in response to its temperature while exhausting.

14. The method of claim 11 including,

controlling the temperature of the fluid enviornment exhausting from thetreatment zone within the temperature range of from about 212F to about980F in response to its temperature while exhausting.

15. The method of claim 11 including,

controtling the enthalpy in the fluid environment to produce apredetermined enthalpy therein before flowing into and indepenzently ofthe treatment zone.

16. The method to claim Ill including,

controlling the enthalpy in the fluid environment to produce apredetermined enthaipy therein at least equal to that of the exhaustingfluid environment before flowing into and independently of thetreatmentzone.

UNITED STATES PATENT OFFICE CERTIFICATE ()F CORRECTION I Patent No.3,744,960 Dated July 10, 1973 Inventor(s) Glen R. Ingels It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

On title page, item [76] inventors name reads "Glen R. Ingels". Itshould read Glenn R. Ingels Column 2, line 10, "and the enthalpy usefulin the reduction" should. read and the enthalpy of the vexhausting fluidenvironment and is especially useful in the reduction Column 3, line 58,"b.t.u.s." should read b.t.u. s

Column 4, line 9, "to structures having highly advantageous" should readto the bodies at treatment temperatures by which new and unusualstructures having highly advantageous Column 4, line 18, "elevation"should read--elevational 1 Column 6, line 7, "coling" shouldread--cooling Column 6, line 37, "D-F-S" should read-D-E- -S Column 9,line 24, "Table VI" should read Table IV Column ll, line 61, "by a themotor" should read by the motor Column 12, line 68, "low" shouldread-flow-- Column 14, line 3, insert "(18 cfh)" after "per hour" Column14, line 15, "undernPath" should read underneath-- F ORM PC4050 (\0-69)USCOMNPDC 60376-P69 h u s. cnvznuusm PHIN'HNG OFFICE 969 0356-334Certificdte of Correction Patent No. 3,744,960 Page 2 cdlumh 14, line16, "0.008" should read .008

Column 15; line 15, "0.010" should read .010

Column 16, line 33, "hour 77 F" should read hour 77 F Signed and. sealedthis 20th day of August 197 (SEAL) Attest:

MCCOY 1 1. GIBSON, JR. c. MARSHALL DANN Attestlng Officer v Commissionerof Patents

2. The method of claim 1 including, controlling the enthalpy of thefluid enviroment before flowing into the treatment zone to produce apredetermined enthalpy in the fluid environment at least equal to thatof the fluid environment exhausting from the treatment zone.
 3. Themethod of claim 1 including, controlling the enthalpy of the fluidenvironment exhausting from the treatment zone in response to itstemperature.
 4. The method of claim 3 including, controlling theenthalpy in the fluid environment entering the treatment zone to producea predetermined enthalpy in the fluid environment before flowing intothe treatment zone at least equal to that of the fluid environmentexhausting from the treatment zone.
 5. A method of altering theproperties of materials in a treatment zone comprising, flowing into thetreatment zone and about the material a fluid environment selected fromthe group consistinG of liquid water saturated with a major amount ofcarbon dioxide, a minor amount of methane, and lesser amounts of carbonmonoxide and hydrogen, and liquid water saturated with a major amount ofcarbon dioxide and lesser amounts of carbon monoxide and hydrogen, whilemaintaining the temperature of the water from about 32*F to about 160*Fand under pressure from ambient atmospheric to 218.5 atmospheres whileflowing into the treatment zone, and exhausting the fluid environmentfrom the treatment zone.
 6. The method of claim 5 including, controllingthe temperature of the fluid environment exhausting from the treatmentzone between about 212*F and about 1,500*F in response to itstemperature while exhausting.
 7. The method of claim 5 including,controlling the temperature of the fluid environment exhausting from thetreatment zone within the temperature range of about 212*F to about400*F in response to its temperature while exhausting.
 8. The method ofclaim 5 including, controlling the temperature of the fluid enviornmentexhausting from the treatment zone within the temperature range of about400*F tO about 980*F in response to its temperature while exhausting. 9.The method of claim 6 including, controlling the enthalpy in the fluidenvironment to produce a predetermined enthalpy therein before flowinginto and independently of the treatment zone.
 10. The method of claim 6including, controlling the enthalpy in the fluid environment to producea predetermined enthalpy therein at least equal to that of theexhausting fluid environment before flowing into and independently ofthe treatment zone.
 11. A method of treating material whose propertiesare altered thereby comprising, generating a fluid environment selectedfrom the group consisting of liquid water saturated with a major amountof carbon dioxide, a minor amount of methane, and lesser amounts ofcarbon monoxide and hydrogen, and liquid water saturated with a majoramount of carbon dioxide and lesser amounts of carbon monoxide andhydrogen while maintaining temperature of the water from 32*F to about160*F and under pressure from atmospheric to 218.5 atmospheres, flowingthe generated fluid environment to a treatment zone while retaining theproperties of the generated saturated fluid, introducing the generatedfluid environment into the treatment zone and about the material therebyproviding a fluid environment about the material in the treatment zoneduring treatment, and exhausting the fluid environment from thetreatment zone.
 12. The method of claim 11 including, controlling thetemperature of the fluid environment exhausting from the treatment zonewithin the temperature of from about 212*F to about 1,500*F in responseto its temperature while exhausting.
 13. The method of claim 11including, controlling the temperature of the fluid environmentexhausting from the treatment zone within the temperature range of fromabout 212*F to about 400*F in response to its temperature whileexhausting.
 14. The method of claim 11 including, controlling thetemperature of the fluid enviornment exhausting from the treatment zonewithin the temperature range of from about 212*F to about 980*F inresponse to its temperature while exhausting.
 15. The method of claim 11including, controlling the enthalpy in the fluid environment to producea predetermined enthalpy therein before flowing into and independentlyof the treatment zone.
 16. The method of claim 11 including, controllingthe enthalpy in the fluid environment to produce a predeterminedenthalpy therein at least equal to that of the exhausting fluidenvironment before flowing into and independently of the treatment zone.